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arXiv · 1811.08621

Super Damping of Mechanical Vibrations

Abstract

We report the phenomenon of coherent super decay, where a linear sum of several damped oscillators can collectively decay much faster than the individual ones in the first stage, followed by stagnating ones after more than 90 percent of the energy has already been dissipated. The parameters of the damped oscillators for CSD are determined by the process of response function decomposition, which is to use several slow decay response functions to approximate the response function of a fast decay reference resonator. Evidence established in experiments and in finite element simulations not only strongly supported the numerical investigations, but also uncovered an unexplored region of the tuned mass damper parameter space where TMDs with total mass less than 0.2 percent of a primary free body can damp its first resonance up to a damping ratio of 4.6 percent. Our findings also shed light onto the intriguing underline connections between complex functions with different singular points.

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Ka Yan Au Yeung, Brian Yang, Liang Sun, Kehang Bai, Z. Yang. 2018-12-03. Super Damping of Mechanical Vibrations. https://arxiv.org/abs/1811.08621

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